Back in Justin's party-turned-bloody-burial chamber, Dean's killing zombies with UWZAs (he has more than one, which is good, because he has more than one zombie). A female ghost shows up and wants to play. She fazes in and out, and then throws Dean against the chamber wall, then disappears. Still on the floor, Dean says, "Zombie-Ghost orgy, huh? Well, that's it. I'm torching everybody." I love a pragmatist.
Meanwhile, the demon still has Sammy by the throat. Struggling, Sam draws The Knife That Can Kill Anything And Actually Does. Look at him trying to be so good. I hope the angels are watching over him! He tries to stick the demon with it, but just hits him sideways, on the arm, and the demon's still wearing Don's jacket, so it doesn't do much damage. The knife and the demon's hand light up a little, but then the demon pushes the knife out of Sam's hand. He throws Sam across the room. As Sam rises, the demon charges at him. Otherwise defenseless, Sam raises his Pimp Hand of Ipecac (credit to KatieJo and AreaWoman in the forums), to ward off the demon and exorcise it with his mind. Sorry, Dean just whispered in my ear, that should be WITH HIS MIND! Sam Hain is a powerful demon, so Sammy's really struggling. Black demonic essence smoke pours out of the demon's gunshot wounds, which is a new twist. Very nice. The demon fights against Sam's power and slowly moves forward.
Dean rushes around the corner. From the other end of the hallway, he can see everything that's going on between Sam and the demon. It stops him dead in his tracks and it's not clear to me if he stops because he's in shock, or because he realizes he can't disturb Sam. I don't think he's angry though. He seems to be taking it all in. The Knife That Can Kill Anything And Actually Does is lying just inside the doorway, several feet from Sam. The huge demon is trying to advance on Sam. Sam is struggling like hell to exorcise it. Sam sees Dean, and it seems to weaken his concentration for a fraction of a second. The demon closes in. Sam redoubles his efforts. He grabs his head with his non-Pimp Hand of Ipecac; he's clearly in pain. Finally, the black demonic essence smoke starts to flow from the demon's mouth, and Sam's nose bleeds as he really pours on the power. The demon finally falls. Poor Sam looks like he's going to cry. He's still in pain, and his cheeks are flushed. He is face looks all of seven years old. Dean looks on in amazement, as the demon essence burns a hole in the mausoleum floor. Sam, afraid and ashamed, searches his brother's face for a reaction. Dean looks at Sammy like he's seeing him for the first time in a long time.